Goal of this project is to develop a reliable and lightweight device for real-time monitoring of NO and NO2 in the clinical environment. Nitric oxide is actively studies as a therapeutic agent in life- threatening diseases affecting neonates, children, and adults. Increasing numbers of clinical trials report successful treatment of cardiovascular and pulmonary diseases. NO is a very potent gas and administration through inhalation requires continuous monitoring. NO2, an oxidation product of NO, is highly toxic, and needs to be monitored for safety purposes. Giner, Inc.'s sensor technology will be adapted to design miniaturized electrochemical NO and NO2 sensors for incorporation into the breathing circuit. The device design will be particularly focused on the placement of sensors close to the patient, for the attachment to either the endotracheal tube, or the face mask. During Phase I in vitro feasibility of the sensor devices was successfully demonstrated regarding measurement qualities and dependence on gas flow and anesthetic interferents. In addition, the feasibility of a novel, lightweight device design was investigated, which is proposed to be developed into a prototype device during Phase II, where it will be evaluated, together with a corporate partner, regarding performance in the clinical environment. PROPOSED COMMERCIAL APPLICATION Therapeutic doses of NO for neonates, children and adults over the range 2 to 100 ppm are actively being investigated for the management of CHD and ARDS; instrumentation is required to monitor NO (and NO2, an oxidation product) in the low ppm range. The NO and NO2 instrumentation can readily be modified for environmental monitoring applications.